What Airline Disasters Teach About Cognitive Impairment Under Stress

Airline disasters often make great case studies on how a series of insignificant errors can build up into catastrophes.

As the following two case studies will illuminate, unanticipated pressures can force your mind to quickly shift to a panic-like state. As it searches frenetically for a way out of a problem, your mind can disrupt your ability to take account of all accessible evidence and attend rationally to the situation in its entirety.

Stress Can Blind You and Limit Your Ability to See the Bigger Picture: A Case Study on Eastern Airlines Flight 401

As Flight 401 began its approach into the Miami International Airport, first officer Albert Stockstill lowered the landing gear. But the landing gear indicator, a green light to verify that the nose gear was correctly locked in the “down” position, did not switch on. (This was later verified to be caused by a burned-out light bulb. Regardless of the indicator, the landing gear could have been manually lowered and verified.)

The flight deck got thrown into a disarray. The flight’s captain, Bob Loft, sent flight engineer Don Repo to the avionics bay underneath the flight deck to verify through a small porthole if the landing gear was actually down. Loft simultaneously directed Stockstill to put the aircraft on autopilot. Then, when Loft unintentionally leaned against the aircraft’s yoke to speak to Repo, the autopilot mistakably switched to a wrong setting that did not hold the aircraft’s altitude.

The aircraft began to descend so gradually that it could not be perceived by the crew. With the flight engineer down in the avionics bay, the captain and the first officer were so preoccupied with the malfunction of the landing gear indicator that they failed to pay attention to the altitude-warning signal from the engineer’s instrument panel.

Additionally, given that the aircraft was flying over the dark terrain of the Everglades in nighttime, no ground lights or other visual cues signaled that the aircraft was gradually descending. When Stockstill eventually became aware of the aircraft’s altitude, it was too late to recover the aircraft from crashing.

In summary, the cause of the Flight 401’s crash was not the nose landing gear, but the crew’s negligence and inattention to a bigger problem triggered by a false alarm.

Stress Can Blind You into Focusing Just on What You Think is Happening: A Case Study on United Airlines Flight 173

United Airlines Flight 173 crashed on December 28, 1978, in comparable circumstances.

When Flight 173’s pilots lowered the landing gear upon approach to the Portland International Airport, the aircraft experienced an abnormal vibration and yaw motion. In addition, the pilots observed that an indicator light did not show that the landing gear was lowered successfully. In reality, the landing gear was down and locked in position.

With the intention of troubleshooting the landing gear problem, the pilots entered a holding pattern. For the next hour, they tried to diagnose the landing gear glitch and prepare for a probable emergency landing. During this time, however, none of the pilots monitored the fuel levels.

When the landing gear problem was first suspected, the aircraft had abundant reserve fuel—even for a diversion or other contingencies. But, all through the hour-long holding procedure, the landing gear was down and the flaps were set to 15 degrees in anticipation of a landing. This significantly increased the aircraft’s fuel burn rate. With fuel exhaustion to all four engines, the aircraft crashed.

To sum up, Flight 173’s crew got preoccupied with the landing gear’s malfunction and harried preparations for an emergency landing. As a result of their inattention, the pilots failed to keep tabs on the fuel state and crashed the aircraft.

Stress Can Derail Your Train of Thought

Under pressure, your mind will digress from its rational model of thinking.

The emotional excitement from fear, anxiety, time-pressure, and stress can lead to a phenomenon known as “narrowing of the cognitive map.” This tunnel vision can restrict your field of mindful attention and impair your ability for adequate discernment.

Situational close-mindedness can constrict your across-the-board awareness of the situation and force you overlook alternative lines of thought.

Idea for Impact: To combat cognitive impairment under stress, use checklists and standard operating procedures, as well as increased training on situational awareness, crisis communication, and emergency management, as the aviation industry did in response to the aforementioned incidents.